Let
x ----> pounds of candy selling for $1.40 per pound
y ----> pounds of candy costing $2.00 per pound
we have the system of equations
x+y=6 -----> x=6-y -----> equation 1
1.40x+2.00y=1.60(6) ----> equation 2
Solve the system of equations
Substitute equation 1 in equation 2
1.40(6-y)+2.00y=9.6
solve for y
8.4-1.4y+2.00y=9.6
0.60y=9.6-8.4
0.60y=1.2
y=2
Find the value of x
x=6-y
x=6-2=4
therefore
pounds of candy selling for $1.40=4
pounds of candy costing $2.00 per pound=2